The use of hearing protective and noise attenuating devices are well known, and various types of devices have been considered. Such devices include earplugs and semi-aural devices partially or completely constructed of foam or rubber materials that are inserted into, or placed over, the ear canal of a user to physically obstruct the passage of sound waves into the inner ear.
Environmental sounds are typically comprised of a mixture of various sound wave frequencies having varying intensities. Selective attenuating earplugs may be provided that allow a wearer to select from multiple performance settings. For example, a low sound attenuating mode may be selected to attenuate impulse noise, such as from a gunshot, while allowing voices or warning signals to pass through to the ear canal of a wearer. A high attenuating mode may be selected to attenuate all sound regardless of intensity. Various selective attenuating earplugs are available, such as COMBAT ARMS earplugs available from 3M Co. of St. Paul, Minn. For example, dual-ended COMBAT ARMS include first and second ends that may be at least partially inserted into an ear canal of a user. Insertion of a first end may provide attenuation of high-impulse noise, while insertion of a second end may provide maximum attenuation. Single-ended COMBAT ARMS earplugs include a rocker cover, for example, that may be switched between an open and closed position. When in an open position, sound is allowed to enter a sound channel of the earplug and pass through a filter that restricts high-impulse noise before entering the ear canal. When the rocker cover is closed, maximum attenuation may be provided for sound at any level.